Various types of manure spreaders are known; basically, they consist of a box structure into which material to be spread is placed, a push-off gate within the box structure for moving the material towards the rear of the box structure where an unloading and spreading mechanism discharges the pushed material. Some spreaders have their unloading and beating mechanism entirely hydraulically operated so that all parts operate automatically in synchronism; such a spreader may be found described, for example, in Canadian Pat. No. 1,048,567 issued Feb. 13, 1979 to Harder. However, the spreader described in this patent, although capable of being converted into a dump box for hauling material, has its beater mechanism permanently affixed to the box structure. The rear end of such spreader is therefore hindered, and consequently limited in use, by the presence of the beaters permanently mounted at the rear of the box structure.